If more than one creature is in play and all the creatures in play go to the graveyard at once (such as with Wrath of God), then all of them are returned at end of turn. [WotC Rules Team 98/10/18] This is because all "leaves play" triggers that check the state of the game check the game state at the time right before the card left play. See Rule A.4.21. [D'Angelo 98/11/17]